1. Technical Field
The invention relates to an information processing apparatus, an information processing method, and a non-transitory computer readable recording medium stored with an information processing program.
2. Description of Related Art
Current trends in data printing industry and services require more effective printing of data that includes numerous bitmap images such as photobooks. In the raster image processing (RIP, or rasterization processing) for bitmap image data, it is necessary to perform color conversion process for each of the pixels constituting the bitmap image data (raster data). Accordingly, the RIP processing for the bitmap image data takes longer processing time than that of the RIP processing for text data and graphic data. Such extended processing time will be more remarkable in proportion to higher resolution of the bitmap image data and increase in the number of pixels constituting the bitmap image data.
In addition, color adjustment processes typically take place many times in the field of production printing, which means that the RIP processes have to be done frequently every time the color adjustment takes place. Accordingly, prolonged RIP processing time introduces the problem of decrease in the efficiency of the entire printing process.
A known approach to the above-identified problem is to compare the resolutions of the bitmap images before and after the RIP process, perform the color conversion process for the bitmap image having the lower resolution, and thereby reduce the number of times of color conversion process and the processing time (for example, see Japanese Patent Application Laid-Open No. H10-191088).
However, in the context of the production printing, print data may be constructed by layering multiple high-resolution bitmap images to provide various filter effects such as blurs and bumps. When such print data is subjected to color conversion processes, the invention disclosed in the above prior-art reference performs color conversion process for each bitmap image data of the layered bitmap images when the bitmap image resolution prior to the RIP processing is lower than the resolution after the RIP processing. Accordingly, in the case of print data constructed by layering multiple bitmap images, the color conversion process is performed numerous times. Further, when the color conversion process is performed for the data constructed by the multiple bitmap images, a bitmap image residing beneath other layered bitmap images is overwritten with these upper bitmap images without being output, which means that the color conversion processes that took place for the overwritten lower-layer is unnecessary causing waste of computation resources.
As such, when the unnecessary color conversion processes take place many times, the processing time required for the RIP processing is prolonged, undermining the efficiency of the entire printing process. This problem will be more noticeable and serious in proportion to increase in the number of layered bitmap images.